Endless belt-type conveyors are used in a variety of applications to move various types of goods and articles from one point to another. They are particularly useful in the agricultural context because of their capability of conveying farm products of different sizes and configurations without damage.
One problem that has arisen, however, in conveying farm products is the incidence of dirt and the like that is carried along with the product prior to processing. The endless conveyor is conventionally driven at one point and requires idler support at various points over its length, and the presence of foreign material, such as the conveyed product or dirt or mud has an adverse effect on the idler supports, particularly in wet conditions when the foreign material turns to mud. Under these circumstances, the mud builds up on the idler rollers and in the guides intended to keep the belt tracking straight and increases their effective diameters. When this occurs with each of a number of idler rollers, particularly where the roller is positioned where the conveyor belt changes direction, the overall length of the travel path for the conveyor belt increases. As a result, the conveyor belt is forced to stretch, creating an inherent weakness that often leads to malfunction and belt or roller breakage. Another cause of failure is that the foreign material may build up unevenly on the rollers and cause their effective diameter to increase unevenly. When this occurs, the conveyor belt is forced to track laterally from its proper line of movement. As a result, there is excessive wear on the edge of the belt and the ends of the belt lacing by the sides of the conveyor frame, creating a weakness that leads to ripping or tearing of the belt, and causing undue wear on the sides of the conveyor frame. Problems of such magnitude result in difficult and expensive repairs, and in any case create significant downtime in the conveying operation.